Transmission lock for automobiles



Jan.. 24, 1933. w. R. T-RETBAR TRANSMISSION LOCK FOR `AUTOMOBLE'S Filed Aug, 2l; 1931 Patented Jan. 24, 1933 UNITED STATES WALTER R. TRETBAR, F GOVANS, MARYLAND TRANSMISSION LOCK FOR AUTOMOBILES Application filed August 21, 1931. SerialNo. 558,510.

This invention relates to locks and has special reference to a transmission lock for automobiles.

One important -object of the invention 1s to improve and simplify the general construction of locks of this description.

A second important object of the invention is to provide an improved form of bolt latch for such locks.

A third important object of the invention is to provide a novel and improved resilient latch actuating arm in locks of this character.

With the above and other objects in view as will be hereinafter apparent, the invention consists in general of certain novel details of construction and combinations of parts hereinafter fully described, illustrated in the accompanying drawing and specifically claimed.

In the accompanying drawing like characters of reference indicate like parts in the several views7 and:

Figure 1 is a section through the lock on the line 1-1 of Figure 3.

Figure 2 is a section on the line 2-2 of Figure 3.

Figure 3 is a plan View of the lock with the casing cover removed and the bolt latched in forward or locking position.

Figure 4 is a view similar to Figure 3 but showing the latch released and the bolt ready to be moved to rearward or unlocked position.

Figure 5 is a section on the line 5-5 of Figure 1.

In the construction of the invention as herein shown. there is provided a casing body having a iioor or bottom which has one end semi-circular and has its other end squared off, the sides of this bottom being parallel. A casing wall flange 11 projects upwardly from the periphery of the bottom and a circular wall or flange 12 projects down- Wardly from the bottom so that the casing may it on and be secured to the tubular upper end of a transmission housing 13. casing cover having a top 14 and a peripheral flange 15 is provided of the same shape as the bottom but slightly larger sothat the {iange 15 ts on the outside of the flange 11 and is there secured by rivets 16. The-top and bottom are provided with alined openings 17 through which passes the gear shift lever 18 of the transmission, this lever being concentric in said openings when in neutral position. f

Extending across the casing in spaced relation to the bottom and parallel thereto is a partition 19 having depending flanges 20 fit- 60 ting against the sides of the casing and there secured by rivets 21. The forward end of this partition is provided With a slot 22 wherethrough passes the lever 18. Fixed on top of the partition adjacent one side of the casing is a long Z-shaped guide bar 23 while adjacent the other side of the casing is a pair of similar but short guide bars 24 which are spaced from each other longitudinally of the casing. A bolt 25 is slidably mounted on 70 the partition between these guide bars` and is Y provided at its forward end with a notch 26 wherein the lever 18 fits when thebolt is in locking or forward position. At its rear portion the bolt is provided with a key receiving opening 26, certain flanges 27 projecting from the sides of the opening to cooperate with the spaces between the wards of a key 28 having spaced wards 29. Latch notches 30 are formed in the side of the bolt 80 between the guides '24 and also located between these guides is a pivot pin 31. Mounted on this pin is the eye of a plate bent to form a two armed lever having one arm 32 provided with a suitable end to engage in a respective notch 30 according to the position of the bolt in locked or unlocked position. The other arm 33 of this lever is normally held against the rear guide 24 by a coiled t spring 34 interposed between the arm 33 and 90 the adjacent sideof the casing. The under side of the bolt is cut away at the rear to provide space for a latch releasing arm 35 which extends rearwardly from the arm 32 and is inclined inwardly toward the center line of 95 the casing. This arm is bent back upon it- A self at 36 and thus forms a U-shaped spring,

the arm being resilient. The extremity of the part 36 is bent inwardly as at 37 toward the part 35 so as to engage this part and form lo a limit to the yielding of the spring arm. The part 36 lies in the path of one of the wards of the key and this ward, in locking and unlocking operations, engages the part .36 and first forces it towards the part 35 until the end 37 engages that part. Then, further movement of the key causes the latch to swing as in Figure 4 to a position of disengagement from the bolt so that the latter can be moved l0 by still further movement of the key whereupon the pressure on the spring arm will `be relaxed and the latch will be engaged in the other notch by the action of spring 34: when d the bolt has completed its movement. la It is to be noted that the upper arm or part ofthe spring 36 normally rests in the position shown in F ig. 3 and thereby restrains the ward of the key from assuming a nearly vertical position. By making this part yieldable the ward may be held well away from the Vertical Without causing undue movement of the part 32 in actuating the lock. Further, by providing the rebent stop portion 37 the movement of the arm 32 will take place in *9 a manner similar to that of a rigid arm. Thus this construction combines the advantages of a yielding arm and a rigid arm at the part 32. 1 There has thus been provideda simple and efficient device of the kind described and for the purpose specified. It is obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit thereof. It is not, therefore, desired to confine the invention to the exact form herein shown and described, but it is desired to include all'such as properly come within the scope claimed.

Having thus described the invention, what is claimed as new, is: Y

In a. lock of the kind described,a key oper- `ated reciprocable bolt movable between locking and unlocking positions, a tumbler lever releasably holding the bolt selectively in .locking and unlocking positions, an arm of resilient material extending from said lever andv having a portion bent backwardly and y lying in the path of a ward of the operating key whereby to form a U-shaped springarm for releasing the lever as the key is turned, and a rebent end on the backwardly bent portion of the spring arm arranged to enw gagethe main portion of said spring arm f W and limit the yielding thereof under in7 fluence of the key. In testimony whereof I aiiix my signature.

WALTER n. TRETBAR. 

